Field of the Invention
The present invention relates to an electrophotographic image forming apparatus (hereinafter, image forming apparatus), a cartridge attachable to and detachable from an apparatus main body of the image forming apparatus, and a member used for the cartridge.
In this case, the image forming apparatus forms an image on a recording medium by using an electrophotographic image forming process. Examples of the image forming apparatus include, for example, an electrophotographic copier, an electrophotographic printer (for example, laser beam printer, LED printer, etc.), a facsimile device, and a word processor.
Also, the cartridge may be a configuration including an electrophotographic photosensitive drum (hereinafter, photosensitive drum) being an image carrying member, or a process unit acting on the photosensitive drum (for example, developer carrying member (hereinafter, developing roller)) in a cartridge form, and is attachable to and detachable from the image forming apparatus. The cartridge may be a configuration in a cartridge form including the photosensitive drum and the developing roller in an integrated manner or a configuration in a multiple-cartridge form including the photosensitive drum and the developing roller in a separate manner. The former configuration including the photosensitive drum and the developing roller is called process cartridge. The latter configuration including the photosensitive drum is called drum cartridge. The latter configuration including the developing roller is called development cartridge.
Description of the Related Art
Conventionally, in an image forming apparatus, a process cartridge system is employed, in which a process unit is integrally formed in a cartridge form and this cartridge is attachable to and detachable from an apparatus main body of the image forming apparatus.
With this process cartridge system, since maintenance of the image forming apparatus can be executed by a user without a service person, usability is markedly increased. Hence, this process cartridge system is widely used in the image forming apparatus.
Conventionally, for the process cartridge system, as a configuration that positions the cartridge with respect to an apparatus main body of the image forming apparatus in the longitudinal direction, there is known a configuration provided with a portion that is fitted to the apparatus main body at an end portion in the longitudinal direction (U.S. Pat. No. 8,050,593 and Japanese Patent Laid-Open No. 2003-330335).